Incidence, characteristics and risk factors for alveolar recruitment maneuver-related hypotension in patients undergoing laparoscopic colorectal cancer resection

Table 3 Univariate analysis of the associations between intraoperative variables and alveolar recruitment maneuver-related hypotension

	ARM-related hypotension		P value
	Yes, n = 34	No, n = 106
Non-PPT ventilation ≥ 90 min	9	17	0.31
Duration of ventilation (min)	233 ± 67	229 ± 84	0.76
Amount of infusion (mL)	3414 ± 799	3181 ± 611	0.13
Recruitment maneuver (times)	7 (6, 8)	7 (5, 8)	0.88
Prefilling fluids before anesthesia (mL)	678 ± 140	696 ± 144	0.52
Blood loss ≥ 150 mL	12	15	0.01
Trendelenburg position	25	79	0.82
Vt at T1 < 7 mL/kg of PBW	8	20	0.62
Vt at T2 < 7 mL/kg of PBW	21	51	0.24
PIP at T1 (cm H2O)	17 ± 2	17 ± 2	> 0.99
PIP at T2 (cm H2O)	24 ± 3	25 ± 2	0.076
PIP at T2 < 24 cm H2O	15	23	0.02
Respiratory rate at T1 (bpm)	12 (12, 12)	12 (12, 12)	0.97
Respiratory rate at T2 (bpm)	17 (16, 18)	16 (15, 18)	0.15
Driving pressure at T1 (cm H2O)	6 ± 2	6 ± 2	0.94
Driving pressure at T2 (cm H2O)	13 ± 2	13 ± 2	0.14
Cdyn at T1 (mL/cm H2O)	48 ± 9	51 ± 14	0.38
Cdyn at T2 (mL/cm H2O)	24 ± 5	24 ± 5	0.95
Urine output < 1.2 mL/kg/h	7	23	0.82
Hemoglobin at T2 (g/L)	97 ± 20	103 ± 18	0.10
lactic acid at T2 (mmol/L)	0.66 ± 0.18	0.69 ± 0.23	0.58

Continuous data are reported as the mean ± SD or median (25^th, 75^th percentile), and categorical data are given as counts. Alveolar recruitment maneuver (ARM)-related hypotension: Mean arterial pressure < 60 mmHg during an ARM or within 5 min after an ARM. PPT: Pneumoperitoneum; ARM: Alveolar recruitment maneuver; PBW: Predicted body weight; T₁: Immediately before induction of pneumoperitoneum; T₂: 0.5 h after induction of pneumoperitoneum; PIP: Peak inspiratory pressure; bpm: Breaths per minute; C_dyn: Dynamic compliance; V_t: Tidal volume.